We have several site-to-site VPNs over here. And we have our employees connecting to our corporate network via VPN clients (you noticed the Cisco stories here on mac geeks). We usually don’t want our VPN clients to access the site-to-site VPNs with there IP range. Only selected internal machines are allow to access the site-to-site VPNs.

So also the allmighty admin has to use proxie machines to dive further into the site-to-site vpns. Although I can configure MacOS X with descent proxie settings, most of the applications (even built-ins) don’t make use of them. Especially the SOCKS proxy isn’t use by SSH.

This is where Proxifier comes in handy. It acts as an filter for traffic and directs all matching traffic through a given Proxy-Server. This can be one or more Proxy servers. You don’t have to modify any of the internet enabled applications. It just works out of the box.

This saves me a lot of time and grey hair.

First you define your proxy servers.

You can choose SOCKS4, SOCKS5 or HTTP(S) proxies, even with authentication

Then you can define rules including or excluding traffic

From now on, all traffic matching your rules will be directed through the given proxy servers.

You get a nice Monitor window showing all active connections and traffic stats.

I’ve got MacOS X 10.5 (Leopard) on my MacBook Pro and use the Cisco VPN-Client very frequently. Basically this works great. But from time to time the VPN-Client software refuses loading because it can’t connect to the VPN subsystem in the MacOS kernel. Showing nothing but this ugly error message.

Until today when I further experimented with the system the only way to get the client working again was reinstalling the software. This only takes a few seconds and doesn’t require a restart. But is annoying anyhow.

But now I found a better workaround, not a solution though. Obviously the MacOS kernel extension doesn’t seem to work when the client shows this error message. So the easiest way should be to simply reload it.

I investigated the following procedure to reload the Cisco VPN kernel extension and make the VPN client work again:

Open the Terminal

become Superuser: sudo su -

go to the kernel extension directory: cd /System/Library/Extensions

unload the CiscoVPN.kext: kextunload CiscoVPN.kext

load the CiscoVPN.kext again: kextload CiscoVPN.kext

your done. The client should work now

[Update 15.12.2007]:
Today I found an update for the Cisco VPN Client on www.macupdate.com
Cisco released the new version on Dec. 6th 2007. The release notes simply state the following: